Create non-blocking broadcaster helper and use it to manage Coordinat…

…or state notifications (#2849)

internal/pkg/agent/application/actions/handlers/handler_action_application.go

@@ -9,8 +9,6 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/elastic/elastic-agent/internal/pkg/agent/application/coordinator/state"
-
 	"github.com/elastic/elastic-agent-client/v7/pkg/client"
 
 	"github.com/elastic/elastic-agent/internal/pkg/agent/application/coordinator"
@@ -171,7 +169,7 @@ func readMapString(m map[string]interface{}, key string, def string) string {
 	return def
 }
 
-func findUnitFromInputType(state state.State, inputType string) (component.Component, component.Unit, bool) {
+func findUnitFromInputType(state coordinator.State, inputType string) (component.Component, component.Unit, bool) {
 	for _, comp := range state.Components {
 		for _, unit := range comp.Component.Units {
 			if unit.Type == client.UnitTypeInput && unit.Config != nil && unit.Config.Type == inputType {

internal/pkg/agent/application/actions/handlers/handler_action_upgrade.go

@@ -54,7 +54,6 @@ func (h *Upgrade) Handle(ctx context.Context, a fleetapi.Action, ack acker.Acker
 	go func() {
 		h.log.Infof("starting upgrade to version %s in background", action.Version)
 		if err := h.coord.Upgrade(asyncCtx, action.Version, action.SourceURI, action, false); err != nil {
-
 			h.log.Errorf("upgrade to version %s failed: %v", action.Version, err)
 			// If context is cancelled in getAsyncContext, the actions are acked there
 			if !errors.Is(asyncCtx.Err(), context.Canceled) {

internal/pkg/agent/application/actions/handlers/handler_action_upgrade_test.go

@@ -51,59 +51,102 @@ func (u *mockUpgradeManager) Ack(ctx context.Context, acker acker.Acker) error {
 }
 
 func TestUpgradeHandler(t *testing.T) {
+	// Create a cancellable context that will shut down the coordinator after
+	// the test.
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
 	log, _ := logger.New("", false)
-	ack := noopacker.New()
 	agentInfo, _ := info.NewAgentInfo(true)
 	msgChan := make(chan string)
-	upgradeMgr := &mockUpgradeManager{msgChan: msgChan}
-	specs := component.RuntimeSpecs{}
-	c := coordinator.New(log, configuration.DefaultConfiguration(), logger.DefaultLogLevel, agentInfo, specs, nil, upgradeMgr, nil, nil, nil, nil, nil, false)
+
+	// Create and start the coordinator
+	c := coordinator.New(
+		log,
+		configuration.DefaultConfiguration(),
+		logger.DefaultLogLevel,
+		agentInfo,
+		component.RuntimeSpecs{},
+		nil,
+		&mockUpgradeManager{msgChan: msgChan},
+		nil, nil, nil, nil, nil, false)
+	//nolint:errcheck // We don't need the termination state of the Coordinator
+	go c.Run(ctx)
+
 	u := NewUpgrade(log, c)
-	ctx := context.Background()
 	a := fleetapi.ActionUpgrade{Version: "8.3.0", SourceURI: "http://localhost"}
+	ack := noopacker.New()
 	err := u.Handle(ctx, &a, ack)
 	require.NoError(t, err)
 	msg := <-msgChan
 	require.Equal(t, "completed 8.3.0", msg)
 }
 
 func TestUpgradeHandlerSameVersion(t *testing.T) {
+	// Create a cancellable context that will shut down the coordinator after
+	// the test.
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
 	log, _ := logger.New("", false)
-	ack := noopacker.New()
 	agentInfo, _ := info.NewAgentInfo(true)
 	msgChan := make(chan string)
-	upgradeMgr := &mockUpgradeManager{msgChan: msgChan}
-	specs := component.RuntimeSpecs{}
-	c := coordinator.New(log, configuration.DefaultConfiguration(), logger.DefaultLogLevel, agentInfo, specs, nil, upgradeMgr, nil, nil, nil, nil, nil, false)
+
+	// Create and start the Coordinator
+	c := coordinator.New(
+		log,
+		configuration.DefaultConfiguration(),
+		logger.DefaultLogLevel,
+		agentInfo,
+		component.RuntimeSpecs{},
+		nil,
+		&mockUpgradeManager{msgChan: msgChan},
+		nil, nil, nil, nil, nil, false)
+	//nolint:errcheck // We don't need the termination state of the Coordinator
+	go c.Run(ctx)
+
 	u := NewUpgrade(log, c)
-	ctx1 := context.Background()
-	ctx2 := context.Background()
 	a := fleetapi.ActionUpgrade{Version: "8.3.0", SourceURI: "http://localhost"}
-	err1 := u.Handle(ctx1, &a, ack)
-	err2 := u.Handle(ctx2, &a, ack)
+	ack := noopacker.New()
+	err1 := u.Handle(ctx, &a, ack)
+	err2 := u.Handle(ctx, &a, ack)
 	require.NoError(t, err1)
 	require.NoError(t, err2)
 	msg := <-msgChan
 	require.Equal(t, "completed 8.3.0", msg)
 }
 
 func TestUpgradeHandlerNewVersion(t *testing.T) {
+	// Create a cancellable context that will shut down the coordinator after
+	// the test.
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
 	log, _ := logger.New("", false)
-	ack := noopacker.New()
 	agentInfo, _ := info.NewAgentInfo(true)
 	msgChan := make(chan string)
-	upgradeMgr := &mockUpgradeManager{msgChan: msgChan}
-	specs := component.RuntimeSpecs{}
-	c := coordinator.New(log, configuration.DefaultConfiguration(), logger.DefaultLogLevel, agentInfo, specs, nil, upgradeMgr, nil, nil, nil, nil, nil, false)
+
+	// Create and start the Coordinator
+	c := coordinator.New(
+		log,
+		configuration.DefaultConfiguration(),
+		logger.DefaultLogLevel,
+		agentInfo,
+		component.RuntimeSpecs{},
+		nil,
+		&mockUpgradeManager{msgChan: msgChan},
+		nil, nil, nil, nil, nil, false)
+	//nolint:errcheck // We don't need the termination state of the Coordinator
+	go c.Run(ctx)
+
 	u := NewUpgrade(log, c)
-	ctx1 := context.Background()
-	ctx2 := context.Background()
 	a1 := fleetapi.ActionUpgrade{Version: "8.2.0", SourceURI: "http://localhost"}
 	a2 := fleetapi.ActionUpgrade{Version: "8.5.0", SourceURI: "http://localhost"}
-	err1 := u.Handle(ctx1, &a1, ack)
+	ack := noopacker.New()
+	err1 := u.Handle(ctx, &a1, ack)
 	require.NoError(t, err1)
 	time.Sleep(1 * time.Second)
-	err2 := u.Handle(ctx2, &a2, ack)
+	err2 := u.Handle(ctx, &a2, ack)
 	require.NoError(t, err2)
 	msg1 := <-msgChan
 	require.Equal(t, "canceled 8.2.0", msg1)